Sublimation of Bi2O3-based materials is an important degradation issue for the long-term applications of many electronic devices. A series of SnO2-doped Bi2O3 materials (SBO), was synthesized, densified, and then tested in air or strong reducing atmosphere. The SnO2-doping effects and sublimation kinetics of the SBO materials were studied by X-ray diffraction (XRD), scanning electron microscope (SEM) and precise mass loss measurement. The results show that formation of Bi2Sn2O7 phase greatly retards the mass loss of SBO. The SBO samples show a surface sublimation in an energy of 52.6 kJ.mol−1. However, the sublimation is also controlled by surface microstructure as the amount of vaporizing species (the Bi or gaseous Bi-oxides) is more than 0.1 mass%. The evaporation is retarded on the rough surface and the mechanism of surface evaporation is changed to diffusional control.

Keywords: Bi2O3, SnO2, Mass loss, Sublimation, Kinetics.